DOI: 10.1002/2017GB005655
Scopus记录号: 2-s2.0-85030540809
论文题名: A model for12CH2D2and13CH3D as complementary tracers for the budget of atmospheric CH4
作者: Haghnegahdar M ; A ; , Schauble E ; A ; , Young E ; D
刊名: Global Biogeochemical Cycles
ISSN: 8866236
出版年: 2017
卷: 31, 期: 9 起始页码: 1387
结束页码: 1407
语种: 英语
英文关键词: 12CH2D2and13CH3D
; atmospheric methane
; clumped isotopes
; isotope signature
; rare isotopes
; ΔCH2D2 and Δ13CH3D
Scopus关键词: atmospheric chemistry
; isotopic analysis
; isotopic composition
; isotopic fractionation
; methane
; model
; source-sink dynamics
; tracer
英文摘要: We present a theoretical model to investigate the potential of13CH3D and12CH2D2, the doubly substituted mass-18 isotopologues of methane, as tools for tracking atmospheric methane sources and sinks. We use electronic structure methods to estimate kinetic isotope fractionations associated with the major sink reactions of methane in air (reactions with OH and Cl radicals) and combine literature data with reconnaissance measurements of the relative abundances of13CH3D and12CH2D2to estimate the compositions of the largest atmospheric sources. This model atmospheric budget is investigated with a simplified box model in which we explore both steady state and dynamical (nonsteady state) conditions triggered by changes in emission or sink fluxes. The steady state model predicts that sink reactions will generate a marked (>100‰) clumped isotope excess in atmospheric Δ12CH2D2relative to the net source composition.12CH2D2measurements may thus be useful for tracing both atmospheric source and sink fluxes. The effect of sinks on Δ13CH3D is much less pronounced, indicating that13CH3D in air will give a more focused picture of the source composition. ©2017. American Geophysical Union. All Rights Reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/77706
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA, United States
Recommended Citation:
Haghnegahdar M,A,, Schauble E,et al. A model for12CH2D2and13CH3D as complementary tracers for the budget of atmospheric CH4[J]. Global Biogeochemical Cycles,2017-01-01,31(9)